Acceptability and Willingness to Use the "CaknaStrok" Mobile Health Application and Associated Factors Among Informal Caregivers of Post-Stroke Patients in Malaysia: Protocol for an Explanatory Sequential Mixed-Methods Study.

Background: Stroke is the third leading cause of death and a major cause of long-term disability in Malaysia, where the continuity of post-stroke care depends heavily on unpaid, untrained informal family caregivers. These caregivers face a well-documented "discharge cliff," assuming complex medical and rehabilitative responsibilities with minimal preparation. The locally developed "CaknaStrok" mobile health (mHealth) application was designed to bridge this support gap. However, the existence of a tool does not guarantee its use; sustained adoption depends on whether caregivers find the application acceptable and are willing to integrate it into an already demanding caregiving routine. Objectives: This protocol describes a study designed to determine the levels of acceptability and willingness to use the CaknaStrok application, to examine the associated predictors (effort expectancy, ability, digital health literacy, and intervention coherence), and to test the central mediating role of acceptability through a novel Integrated Acceptability-Willingness (IAW) Framework. Methods: An explanatory sequential mixed-methods design will be conducted at the Stroke Ward of Hospital Canselor Tuanku Muhriz (HCTM), a World Stroke Organization-certified Advanced Stroke Centre. In Phase I, a target of 200 informal primary caregivers will be recruited through consecutive sampling and surveyed using a validated, bilingual (Malay/English) self-administered questionnaire that operationalises the IAW constructs through three established instruments (UTAUT, the Digital Health Literacy Instrument, and the Theoretical Framework of Acceptability). Following a standardised facilitated onboarding, caregivers use the application ad libitum for four to six weeks before completing the questionnaire. Expected Results: The study will quantify caregiver acceptability and willingness to use, identify which factors most strongly drive acceptance, and empirically test whether acceptability mediates the relationship between the predictors and willingness to use. Qualitative themes will contextualise the statistical pathways, surfacing culturally specific mechanisms of adoption that single-method designs typically miss. Ethical approval was obtained from the UKM Research Ethics Committee (JEP-2024-392). Conclusions: This study is expected to generate context-sensitive evidence to guide the design of caregiver-facing mHealth interventions and inform future multi-site implementation and policy development efforts within the Malaysian stroke-care pathway.